This invention relates to a connector for a flat circuit member, and more particularly to a flat circuit member connector in which an electrical contact portion, formed at an end portion of a flexible flat circuit member, is wound around a front end portion of a holder, and the front end portion of this holder is fitted and inserted into a terminal receiving portion of a connector housing, thereby electrically connecting conductors respectively to electrical connection terminals held in the terminal receiving portion.
FIG. 7 shows a related connector for a flat circuit member.
In the state that a connector connection portion (electrical contact portion) 3, formed at an end portion of a rigid flat circuit member in the form of a printed circuit board 2, is inserted into a slit-like terminal receiving portion 6 of a connector housing 5 of this flat circuit member connector 1, resilient contact piece portions 8a of a plurality of pairs of opposed electrical connection terminals 8, 8, provided within the terminal receiving portion 6, hold the connector connection portion 3, and conducting portions (conductors) 11, provided at the connector connection portion 3, are electrically connected to the corresponding electrical connection terminals 8, respectively.
Side limitation surfaces 6a for abutting against opposite side surfaces of the electrical connection terminals 8 to limit the lateral movement of the electrical connection terminals 8, and rear limitation surfaces 6b for abutting against rear surfaces of the electrical connection terminals 8 are formed within the terminal receiving portion 6 of the connector housing 5. The electrical connection terminals 8 are positioned and held against shaking by the side limitation surfaces 6a and the rear limitation surfaces 6b. 
However, in the above flat circuit member connector 1, when the connector connection portion 3 is inserted into the terminal receiving portion 6, this connector connection portion 3, in some cases, is partially contacted hard with the corresponding electrical connection terminals 8, thus causing an excessive rubbing engagement (interference) therebetween.
When such an excessive rubbing engagement occurs, the resilient contact piece portions 8a of those electrical connection terminals 8, subjected to the excessive rubbing engagement, are resiliently deformed in a larger amount than those electrical connection terminals 8, not subjected to the excessive rubbing engagement, and the connector connection portion 3 are inserted.
Therefore, the flat circuit member connector 1 varies in the inserting pressure acting on the connector connection portion 3 of the printed circuit board 2, and therefore there is encountered a problem that the operation of inserting the printed circuit board 2 is made difficult.
The resilient contact piece portions 8a of part of the electrical contact terminals 8 are excessively deformed because of the excessive rubbing engagement, and as a result the contact positions and contact areas of the resilient contact piece portions 8a are delicately varied, thus inviting a fear that the electrical connection characteristics are degraded.
Therefore, there has been proposed a flat circuit member connector 10 as shown in FIG. 8.
In this flat circuit member connector 10, when the connector connection portion (electrical contact portion) 3, formed at the end portion of the rigid printed circuit board 2 (shown in FIG. 7), is inserted into a slit-like terminal receiving portion 13 of a connector housing 12, a plurality of pairs of opposed electrical connection terminals 18, 18, provided within the terminal receiving portion 13, hold the connector connection portion 3, and conducting portions (conductors) 11, provided at the connector connection portion 3, are electrically connected respectively to the electrical connection terminals 18 disposed in opposed relation thereto.
As shown in FIG. 9, the electrical connection terminal 18 is formed by bending a thin metal sheet into a box-like shape, and a mounting pin 14c is formed at a lower end thereof, and an upper portion thereof is bent back into a bow-like shape to form a resilient contact piece portion 14d. A left side wall 14a and a right side wall 14b are formed by bending, and generally hold the resilient contact piece portion 14d therebetween from opposite (left and right) sides thereof.
Thus, the side walls 14 are formed to cover base portions of the resilient contact piece portion 14d, including the bent portion thereof, and an apex portion of this resilient contact piece portion 14d projects forwardly (right in FIG. 9) beyond the side walls 14. As top per piece portion 14e is formed inwardly of the resilient contact piece portion 14d (on the inner side of the side wall 14), and limits the excessive flexing of the resilient contact piece portion 14d. 
Namely, when an external force acts on the resilient contact piece portion 14d in a direction other than a proper flexing direction because of an excessive rubbing engagement of the printed circuit board 2, the movement of the resilient contact piece portion 14d is limited by the side walls 14a, 14b. When a large external force, greater than a predetermined level, acts on the resilient contact piece portion, the movement thereof is limited by the stopper piece portion 14e, and by doing so, the deformation of the resilient contact piece portion is prevented.
The above printed circuit board 2 is the rigid flat circuit member. Recently, instead of the printed circuit board 2, there has been used a flexible flat circuit member such as a flexible printed circuit member (hereinafter referred to as xe2x80x9cFPCxe2x80x9d), having a wiring circuit printed on a film-like, thin flexible insulative substrate, and a flexible flat cable (hereinafter referred to as xe2x80x9cFFCxe2x80x9d).
In the case of using such a flat circuit member such as an FPC and an FFC, there is used a connector for a flat circuit member. In this case, an electrical contact portion formed at an end portion of the flat circuit member is wound around a front end portion of a holder, and the front end portion of this holder is fitted and inserted into a terminal receiving portion of a connector housing, so that electrical connection terminals held in the terminal receiving portion holds conductors on the electrical contact portion, and therefore are electrically connected thereto.
Namely, the electrical contact portion formed at the end portion of the flexible flat circuit member is wound around the front end portion of the holder, and by doing so, the electrical connection terminals, held in the terminal receiving portion, can hold the conductors on the electrical contact portion, and therefore can be electrically connected thereto.
However, even in the case of employing the electrical connection terminals 18 in the flat circuit member connector 10, there is a possibility that the excessive rubbing engagement is caused by a combination of various factors such as delicate inclination of the connector connection portion 3 at the time of insertion into the terminal receiving portion 13, variations in the accuracy of positioning of the electrical connection terminals 18 in the terminal receiving portion 13, and dimensional irregularities of the electrical connection terminals 18.
Namely, when the connector connection portion 3 of the printed circuit board 2 is inserted into the terminal receiving portion 13, a large force, in some cases, acts on this connector connection portion and the left and right side walls 14a and 14b (formed by bending) and stopper piece portions 14e of the electrical connection terminals 18 because of the excessive rubbing engagement. This causes variations in the inserting pressure, acting on the connector connection portion 3, thus inviting a problem that the operation of inserting the printed circuit board 2 is made difficult.
The same problem is encountered with the electrical connection terminals also in the case where the front end portion of the holder, around which the electrical contact portion formed at the end portion of the flat circuit member is wound, is fitted and inserted into the terminal receiving portion of the connector housing, so that the electrical connection terminals, received and held in the terminal receiving portion, hold the conductors on the electrical contact portion, and are electrically connected thereto.
Therefore, it is an object of this invention to solve the above problems, and more specifically to provide a flat circuit member connector which prevents the deformation of electrical connection terminals, received in a terminal receiving portion of a connector housing, and has good electrical connection characteristics and fitting operability.
In order to solve the aforesaid object, the invention is characterized by having the following arrangement.
(1) A flat circuit member connector comprising:
a connector housing;
a terminal receiving portion provided to the connector housing and including a terminal support portion;
an electrical connection terminal inserted into and received in the terminal receiving portion in an insertion direction, the electrical connection terminal including,
a holding portion disposed in the terminal receiving portion so that a clearance for allowing a displacement of the holding portion in a holding direction is formed between the holding portion and the terminal receiving portion, and
a fixing portion supported by the terminal support portion and extending from the holding portion in the insertion direction,
a flexible flat circuit member including at an end portion thereof an electrical contact portion to which a conductor is exposed; and
a holder which holds the flexible flat circuit member which is would around an end portion of the holder, and is held by the holding portion in the holding direction so that the electrical contact portion is electrically connected to the electrical connection terminal when the holder is inserted into the connector housing in the insertion direction.
(2) The flat circuit member connector according to (1), wherein a weak portion for allowing a pivotal displacement of the holding portion in the holding direction is formed between the fixing portion and the holding portion.
(3) The flat circuit member connector according to (1), wherein a plurality of the terminal receiving portions for respectively receiving a plurality of the electrical connection terminals are provided to the connector housing and are aligned in a direction substantially perpendicular to the holding direction.
(4) The flat circuit member-connector according to (1), wherein the holding portion includes a pair of holding pieces for electrical connection with the electrical connection portion, and the holding portion is disposed in the terminal receiving portion so that the clearance is formed between one of the pair of holding pieces and an inner wall of the terminal receiving portion and between the other holding piece and the inner wall of the terminal portion.
In the above construction, the holding portion of electrical connection terminal, received in the terminal receiving portion of the connector housing, can be pivotally displaced in the holding direction about a pivotal point disposed in the vicinity of the fixing portion fixedly supported by the terminal support portion of the connector housing.
Therefore, even if the holder is inclined relative to the holding portion during the time when the front end portion of the holder, around which the electrical contact portion of the flat circuit member is wound, is fitted and inserted into the connector housing, the holding portion can be pivotally displaced in accordance with the direction of insertion of the holder. Therefore, the front end portion of the holder will not cause an excessive rubbing engagement relative to the holding portion.
On the other hand, even when part of the front end portion of the inserted holder is contacted hard with the holding portions of the corresponding electrical connection terminals because of variations in the dimensional accuracy of the electrical connection terminals (received in the terminal receiving portion of the connector housing) and variations in the accuracy of positioning of the electrical connection terminals in the terminal receiving portion, the relevant holding portions can be pivotally displaced in accordance with the direction of the front end portion of the holder, and therefore the front end portion of the holder will not cause an excessive rubbing engagement relative to these holding portions.
Namely, the elimination of the excessive rubbing engagement of the electrical connection terminal is achieved by the pivotal displacement of the holding portion about the pivotal point near to the fixing portion of the electrical connection terminal, and does not depend on the resilient deformation of the holding portion. Therefore, the inserting pressure, required when inserting the front end portion of the holder into the holding portions of the electrical connection terminals, is generally uniform over all of the electrical connection terminals received in the terminal receiving portion, and variations of the inserting pressure due to the excessive rubbing engagement will not occur.
The holding portion of the electrical contact terminal, holding the front end portion of the holder, will not be contacted hard with this front end portion, and therefore will not be excessively deformed, and each holding portion can contact the conductor on the flat circuit member, wound around the front end portion of the holder, within the predetermined resilient-deformation range.
The term xe2x80x9cweak portionxe2x80x9d means such a portion as a constricted portion and a thinned portion, slightly lower in strength so that it can be easily bent upon application of an external force.